1. Field
Exemplary embodiments of the present invention relate to a display device and a driving method thereof. More particularly, exemplary embodiments of the present invention relate to a display device for measuring an accurate pixel current by compensating a leakage current, and a driving method thereof.
2. Discussion of the Background
An organic light emitting diode (OLED) display uses an OLED for controlling luminance by controlling a current or voltage. The OLED includes an anode layer and a cathode layer for forming an electric field, and an organic light emitting material emits light by controlling the electric field.
Generally, the organic light emitting diode display is classified, according to the driving method, as a passive matrix OLED (PMOLED) or an active matrix OLED (AMOLED). Of these, in view of resolution, contrast, and operation speed, the AMOLED is mainly used. The AMOLED is selectively turned on for every unit pixel.
An organic light emitting diode tends to degrade with use over time, resulting in an emission amount controlled by the pixel current of the degraded organic light emitting diode which may be different from the emission amount at an initial stage. Accordingly, image quality of the organic light emitting device is degraded.
Various methods for compensating the degradation of the organic light emitting diode have been developed. One of them is a method for measuring a pixel current to detect a degree of degradation of the organic light emitting diode. When the pixel current is measured, a leakage current is included in the measured pixel current. When the leakage current is compensated in the measured pixel current, an accurate pixel current is measured, but it is not easy to accurately measure the leakage current.
Further, organic light emitting devices have recently increased in width, thereby resulting in an increase in resistance and capacitance components, and an increase in the time for measuring the pixel current. As a result, there is also an increase in the difficulty in measuring the pixel current and accurately detecting the degradation of the organic light emitting diode.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and, therefore, it may contain information that does not constitute the prior art.